We received our first shipment of the new Grand Bois Lierre (Ivy) 38 – 584 mm (650B x 38 mm) tires. I put a set on my Grand Bois Urban Bike and went for a ride. With the shallow “negative” tread, the Lierre is a very smooth-riding, quiet tire. It offers excellent cornering thanks to its rounds profile and grippy rubber – like all tires we sell. After I got back, I measured its width at 37.6 mm. I expect it to grow to a full 38 mm after a few weeks, so that is what we’ll call it, even if the package says 36 mm. The two samples I put on the scale weighed 364 g and 370 g, respectively.

How does the new Lierre compare to other wide 650B tires?

Compared to the Grand Bois Hetre, the 3 mm smaller width means that shock absorption isn’t quite as good on bigger bumps – the Hetre has 16% more air volume, and you can feel the difference. On the other hand, it’s much easier to build a bike that fits these tires and fenders with adequate clearances (and without resorting to cranks with ultra-wide tread/Q factor), whereas the Hetre requires all clearances to be just right.

How does the Lierre compare to the Pacenti Pari-Moto? Both are similar in width and both use the same casing (made by Panaracer). The biggest difference is the extra 0.5 mm tread of the Grand Bois tires. That roughly doubles the available tread you can wear down until the tire gets so thin that it punctures easily and should be replaced – so these tires should last twice as long. As a result of the extra tread, the Lierre is slightly heavier (+ 65 g) and probably rolls a bit slower. Of course, all tires get lighter and faster as they wear, so a well-worn Lierre should roll as fast as a new Pari-Moto. The Pari-Moto was designed as a special event tire. It’s great for that application. For everyday use, I prefer the Grand Bois.

If you still are unconvinced of the appeal of wide, supple tires that allow you to ride at speed and in comfort on almost any road surface, find somebody whose bike is equipped with these tires, and take it for a spin! Here is more info on the Lierre and other Grand Bois tires.